Incinerators



E. P. BUCKLE INCINERATORS Nov. 10, 1964 Filed May 1, 1962 5 Sheets-Sheet1 FIG. I.

Nov. 10, 1964 Filed May 1, 1962 E. P. BUCKLE INCINERATORS FIG.2.

E. P. BUCKLE 3,156,199

INCINERATORS Nov. 10, 1964 Filed May 1, 1962 5 Sheets-Sheet 3 JL Q Nov.10, 1964 E. P. BUCKLE 3,156,199

INCINERATORS Filed May 1, 1962 5 Sheets-Sheet 4 F|G.4- |s i w 24 u '4 aUnited States Patent 3,156,199 INCINERATORS Ernest Percy Buckle,Pemberton & Sturgess (Gt. Britain) Ltd., Granville Works, CoronationRoad, Park Royal, London NW. 10, England Filed May 1, 1962, Ser. No.191,589 9 Claims. (Cl. 110-8) The invention relates to incinerators andto the parts thereof, and particularly relates to incinerators of thekind described in my prior United States Patent No. 2,763,760.

The invention has among its objects to improve the construction andefiiciency of such incinerators, and particularly to provide anincinerator which is effective to burn damp or moisture-containingmaterials, as well as dry combustible substances.

In hospitals and particularly in the surgical wards, the destruction anddisposal of Waste matter and material, which is generally damp or wet,is both time taking and expensive. In the rush of work it is notpossible for the surgical and nursing staff to give time to checking thedisposal of such matter and as a result, therefore, it frequentlyhappens that the waste matter is thrown into bins or such containerswhich are then emptied into a furnace or incinerator outside the Ward ortheatre during the night when the rush of work is over.

It is advantageous both economically and hygienically if such Wastematerial can be passed direct to the incinerator and burnt immediately.

Furthermore such material is frequently infected and harmful if touched.

It is among the objects of the invention to provide an incinerator inwhich the heating elements can be removed and replaced as for example incase of a breakdown with out any contact or interference with a chargewhich may be in the combustion chamber of the incinerator.

It is further among the objects of the invention to provide anincinerator which ensures a complete breaking down of the carbonaceoussubstances burnt, so that the gases evolved are free of such substancesand there is a minimum extent of pollution of the atmosphere.

A further object of the invention is to provide an incinerator whichoperates economically in the use of the heat required to effect theburning.

A still further object of the invention is to provide an incinerator inwhich those parts which are likely to be affected by heat are sodisposed or otherwise provided relatively to the other parts of theincinerator, that the heat effect is'reduced or eliminated.

According to the invention an incinerator is provided for burning wet,damp, or otherwise moisture-laden material, as well as dry material,comprising a combustion chamber mounted in spaced relation to an outercasing, and means for cooling the outer casing by circulation of airand/or gases and for withdrawing the gases of combustion by an induceddraught, one or more electrical heating elements connected to a sourceof electrical supply being provided at or near thebase of the combustionchamber of the incinerator, the elements being adapted to provide agreater or lesser amount of heat as required, means for shrouding theelements being provided to protect the elements from the material beingburnt and to enable the removal or introduction of one or more elementsto be effected without contact with the combustion chamber or itscontents.

Thus the heating elements may be constructed of resistance wire, suchas, for example, a nickel chromium or other high temperature electricalresistance wire, spirally wound on to a rod or tubular former of ceramicmaterial, such as that sold under the registered trademark Sintox, lyingwithin a tubular, open ended shroud of similar ceramic material andpositioned in such a manner as to span the walls of the combustionchamber in which the material to be burnt is introduced, the ends of theshroud projecting through the walls of the chamber. The spirally woundelement and the former are in troduced into the shroud externally, andthe electrical supply made to these ends.

By such a construction a fully replaceable element is provided withoutthe necessity of internally dismantling, touching, or disturbing thecontents of the combustion chamber which may be physically harmful, asfor example, infectious, poisonous or corrosive material.

Furthermore, without the necessity of varying the simple formation ofthe element and former shrouds of alternative shape, such as an aerofoilouter shape can be used, so as to apply the internally generated heat tobest advantage.

In addition cheapness in replacement is ensured as only the spiralelement itself need be renewed, the original shroud and former beingretained, while by using a ceramic shroud the element is protected fromchemical erosion resulting from contact with the material, the shrouditself being impervious to chemical attack partic ularly from acids,sulphur and by oxidization.

By a suitable choice of components such a heat source can be used togenerate and withstand relatively high temperatures in the region of1350 C. for long periods of service, while by use of ceramics, havinghigh thermal conductivity characteristics and with the shroud in closerelation to the element spiral, rapid heat transfer takes place. Inoperation the temperature difference between the outer surface of theshroud and the element itself is extremely small, thus utilizing to thefull the power input.

According to the invention furthermore, means are provided, when the lidis opened, for effecting the switching on of the burning means which areeffective to complete the circuit of a timing unit and thus to completethe circuit of the electrical heating elements, without the necessityfor linkage, the timing unit operating after a predetermined time to cutoff the supply of current to the heating elements. Thus, one of the pairof pivoted parallel arms supporting the lid may be caused to bearagainst a pivoted arm of the timing unit in such manner as to cause theelectrical circuit of the heating elements to be completed.

The electrical circuit may be so provided as to be adapted for switchingon one or more of the heating elements in accordance with the amount ofheat required to effect the burning.

According to the invention moreover, a fan is provided by means of whichthe products of combustion are withdrawn from the combustion chamber,the fan being.

mounted at a position remote from the heating elements.

According to the invention furthermore, an air duct from the fan to aVenturi fitting is provided and is formed bent at an angle in order toprevent soot or other impurities from falling down an outlet duct andfouling the fan and/ or its driving motor.

According to the invention furthermore, a shaker or riddling means forthe incinerator may comprise a series of parallel bars mountedtransversely of and at their midposition on a supporting rod, the barsbeing adapted to be rocked in a vertical plane between parallel, spaced,fixed bars forming the grate of the incinerator, one end of the rodprojecting from the front of the furnace and being resiliently held in astable position, with the movable bars hroizontal, by means such as twohelical or coil springs secured respectively to the projecting end ofthe rod, and to equi-distant fixed projections on the outer casing ofthe incinerator, whereby the shaker or riddling means can readily berocked from side to side against the resilient pressure exerted by thesprings thus riddling the furnace.

(T! as The invention further comprises the features of constructionhereinafter described.

The invention is diagrammatically illustrated by way of example in theaccompanying drawings in which:

FIGURES l and 3 are end elevations;

FIGURE 2 is a front elevation; and

FIGURE 4 is a rear elevation of an incinerator constructed according tothe invention;

FIGURE is a plan view, partly in section, of the mounting of the heatingelements.

In carrying the invention into eflect, according to the constructionillustrated, the incinerator 1 is of rectangular form mounted on skids2.

The combustion chamber opening 3 is provided at the top of theincinerator 1, with a rearward inclination. The combustion chamberopening is provided with a rectangular frame of heavy, metalconstruction with the lower edge preferably of'arcuate form tofacilitate the emptying of a bucket or other container, containing thematerial to be burnt, and so that the container may be banged againstthe lower edge of the frame to ensure con plete emptying of thecontainer without damage to the incinerator.

The sliding lid 4 which is of arcuate section is supported on twoparallel arms 5 pivoted to the side of the incinerator andcounter-balanced so that the lid always seeks a position of stableequilibrium with the lid closed. Pressure of a foot or bar (not shown)provided at the base of the incinerator is effective through appropriatelinkage (not shown) to operate the lid 4 while leaving both hands freefor emptying container into the incinerator. Alternatively a handle 24-may be provided for operating the lid 4.

Mounted on the upper edge of one of the pivoted lidsupporting arms 5 isa metal bracket 6 so disposed as in the open position of the lid 4, toengage the crankedarm 7 of a timing unit 8 of any suitable construction,mounted at a convenient position on a bracket 9 secured on the rear wallof the incinerator, so that the timing unit 8 is switched on to switchon the electric heating current circuit for a predetermined period. Itwill thus be understood that the opening of the incinerator lid 4 toempty into it more material to be burnt automatically switches on theelectrical heating circuit and sets in operation the timing unit 8 whichis set to switch-oi the heating current after a determined period,without the necessity for any linkage. It will also be understood thatthe timing unit 8 is positioned to the rear of the incinerator at aposition where it will be least affected by the heat evolved in theincinerator.

The combustion chamber is lined with high heat-resisting refractorymaterial.

A flue pipe it) is provided at the top and to the rear of theincinerator, the flue pipe being in vertical alignment with the outletpipe 14 from a blow fan 11, driven by an electric motor 12. both theblower fan ill and the electric motor 12 being mounted on the rear wallof the incinerator at a position in the incinerator as far away fromheatin g elements 13 as possible.

The flow of air caused by the fan 11 serves to efiect the circulation ofcool air in the space between the combustion chamber and the outercasing and also draws the air carrying the products of combustionthrough the flue outlet into the flue pipe lit) by means of any suitableVenturi tube or fitting mounted in the flue outlet 15.

The blower outlet pipe 14 from the blower fan 11 to the flue outlet 15may be bent at right angles enabling the blower fan 11 to be positionedso as to prevent ash or soot falling from the flue pipe lit) into theblower fan 11.

Each of the heating elements 13 is formed of a high heat-resisting wiresuch for example as a nickel chromium wire under the registeredtrademark Kanthal, is helically wound as shown at on a cylindricalsupport 26 and is received within one of the open-ended cylinders 16constructed of a hard ceramic material such for example as that marketedand sold under the registered trademark Sintox and is mounted in a frameor container 22, the ends of the shrouds projecting through the walls ofthe container. The elements with their coverings extend into the furnaceat a position immediately above the riddling means or shaker havingtransverse elements or bars ll? secured on a shaker shaft 18 and adaptedto rock in the spaces between the heating elements, during the rid dlingoperation.

Means for shaknig and riddling the ash operable from outside areprovided so that no opening or disturbance of the incinerator isnecessary. Thus the shaker shaft 18 is supported at one end in a bearingIda and has a shaker handle 19 secured thereon at the other end outsidethe incinerator. The shaker handle 19 is resiliently held by a pair ofcoil springs 23 is a stable position so that the rockable shaker bars1'7 are maintained in a horizontal position when not in use. One end ofeach of the springs 23 is attached to the shaker handle 19 and one endto each of two equi-distant fixed projections on the outer casing of theincinerator. An ash drawer'Zt) is provided which may be withdrawn by ahandle 21 from the space below that containing the material to be burnt,the container for the heating elements and the shaker.

The elements are connected through leads to a source of current supply.

Instead of cylindrical coverings, a flat or curved plate formed ofsuitable ceramic material may be mounted above and optionally below theheating elements. No limitation is involved as to the form the shroud orcovering should take provided only that heating elements are readilyremovable therefrom for replacement or repair from positions external ofthe incinerator, and without disturbance or contact with any undestroyedmatter within the combustion chamber. I

The elements 13 may be electrically connected so that one or more may beconnected in series for light or heavy duty burning.

I claim:

1. An incinerator for burning dry or moisture-laden material, comprisinga combustion chamber mounted in spaced relation to an outer casing,means for cooling the outer casing by circulation of air and forwithdrawing the gases of combustion by an induced draught, a pluralityof electrical heating elements connected to a source of electricalsupply, said heating elements positioned near the base of saidcombustion chamber, ceramic shroud means protecting each of said heatingelements from the material being burned, said shroud means mounted inclose spaced relationship to said heating elements and extending throughthe walls of said combustion chamber, whereby said heating elements maybe replaced externally of said incinerator without contacting saidcombustion chamber. 7

2. An incinerator according to claim 1 wherein said ceramic shroud meanscomprises a plate.

3. An incinerator according to claim 1, wherein said ceramic shroudmeans comprises an open ended cylinder.

4. An incinerator according to claim 1, wherein said heating elementscomprise an electrical coil helically wound about a ceramic supportingmember and wherein the supply of heat is varied by resistances in theelectrical circuit.

5. An incinerator according to claim 1, including riddling means forremoving ash from said combustion chamber comprising a series of barsmounted adjacent said heating elements and adapted to rock in a verticalplane, the movement of said bars being effected by means outside saidincinerator and without the necessity of opening said incinerator, saidbars being resiliently held in a stable horizontal position by springmeans.

6. An incinerator comprising a furnace made of ceramic substance, saidfurnace having an opening through which material to be burned isprojected, said opening being covered by a movable lid, a casingsurrounding said furnace to leave an air space between said furnace andsaid casing, an air inlet and an air outlet to said furnace and to saidcasing, a plurality of heating elements, a fan, an electric motordriving said fan and a clock motor, all mounted within said casing andall in electrical communication with one another, switching meansoperable to close a switch on opening the lid of said furnace tocomplete a circuit to cause operation of the heating element and of saidmotor driving the fan to draw air through said air space into saidfurnace and to extract combustion gases from said furnace through saidoutlet, the improvement therein comprising: shroud means protecting saidheating elements from the material being burned, said shroud meansmounted in close spaced relationship to said heating elements andextending through the walls of said combustion chamber, whereby saidheating elements may be replaced externally of said incinerator withoutcontacting said combustion chamber.

7. An incinerator comprising a furnace made of ceramic substance, saidfurnace having an opening through which material to be burned isprojected, said opening being covered by a movable lid, a casingsurrounding said furnace to leave an air space between said furnace andsaid casing, an air inlet and an air outlet to said furnace and to saidcasing, a plurality of heating elements, a fan, an electric motordriving said fan and a clock motor, all mounted within said casing andall in electrical communication with one another, switching meansoperable to close a switch on opening the lid of said furnace tocomplete a circuit to cause operation of the heating elements and ofsaid motor driving the fan to draw air through said air space into saidfurnace and to extract combustion gases from said furnace through saidoutlet, the improvement therein comprising: ceramic shroud meansprotecting said heating elements from the material being burned, saidceramic shroud means mounted in close spaced relationship to saidheating elements and extending through the walls of said combustionchamber, whereby said heating elements may be replaced externally ofsaid incinerator without contacting said combustion chamber.

8. An incinerator comprising a furnace made of ceramic substance, saidfurnace having an opening through which material to be burned isprojected, said opening being covered by a movable lid, a casingsurrounding said furnace to leave an air space between said furnace andsaid casing, an air inlet and an air outlet to said furnace and to saidcasing, a plurality of heating elements, a fan, an electric motordriving said fan and a clock motor, all mounted within said casing andall in electrical communication with one another, switching meansoperable to close a switch on opening the lid of said furnace tocomplete a circuit to cause operation of the heating elements and ofsaid motor driving the fan to draw air through said air space into saidfurnace and to extract combustion gases from said furnace through saidoutlet, the improvement therein comprising: ceramic shroud meansprotecting said heating elements from the material being burned, saidshroud means comprising a ceramic cylinder open at both ends and mountedin close spaced relationship to said heating elements, said open ends ofsaid ceramic cylinder extending through the walls of said combustionchamber, whereby said heating elements may be replaced externally ofsaid incinerator without contacting said combustion chamber.

9. An incinerator comprising a furnace made of ceramic substance, saidfurnace having an opening through which material to be burned isprojected, said opening bein covered by a movable lid, a casingsurrounding said furnace to leave an air space between said furnace andsaid casing, an air inlet and an air outlet to said furnace and to saidcasing, a plurality of heating elements, a fan, an electric motordriving said fan and a clock motor, all mounted within said casing andall in electrical communication with one another, switching meansoperable to close a switch on opening the lid of said furnace tocomplete a circuit to cause operation of the heating elements and ofsaid motor driving the fan to draw air through said air space into saidfurnace and to extract combustion gases from said furnace through saidoutlet, the improvements therein comprising: ceramic shroud meansprotecting said heating elements from the material being burned, saidceramic shroud means mounted in close spaced relationship to saidheating elements and extending through the Walls of said combustionchamber, whereby said heating elements may be replaced externally ofsaid incinerator Without contacting said combustion chamber; andriddling means for removing ash from said combustion chamber comprisinga series of bars mounted adjacent said heating elements and adapted torock in a vertical plane, the movement of said bars being effected bymeans outside said incinerator and without the necessity of opening saidincinerator, said bars being resiliently held in a stable horizontalposition by spring means.

References Cited in the file of this patent UNITED STATES PATENTS2,064,953 Serpas Dec. 22, 1936 2,110,804 Ludi et a1 Mar. 8, 19382,194,490 Zimmerman Mar. 26, 1940 2,534,953 Curry Dec. 19, 19502,693,774 Knowles Nov. 9, 1954 2,763,760 Buckle Sept. 18, 1956 2,846,557Schulze et al Aug. 5, 1958 2,854,557 Triggs Sept. 30, 1958

1. AN INCINERATOR FOR BURNING DRY OR MOISTURE-LADEN MATERIAL, COMPRISINGA COMBUSTION CHAMBER MOUNTED IN SPACED RELATION TO AN OUTER CASING,MEANS FOR COOLING THE OUTER CASING BY CIRCULATION OF AIR AND FORWITHDRAWING THE GASES OF COMBUSTION BY AN INDUCED DRAUGHT, A PLURALITYOF ELECTRICAL HEATING ELEMENTS CONNECTED TO A SOURCE OF ELECTRICALSUPPLY, SAID HEATING ELEMENTS POSITIONED NEAR THE BASE OF SAIDCOMBUSTION CHAMBER, CERAMIC SHROUD MEANS PROTECTING EACH OF SAID HEATINGELEMENTS FROM THE MATERIAL BEING BURNED, SAID SHROUD MEANS MOUNTED INCLOSE SPACED RELATIONSHIP TO SAID HEATING ELEMENTS AND EXTENDING THROUGHTHE WALLS OF SAID COMBUSTION CHAMBER, WHEREBY SAID HEATING ELEMENTS MAYBE REPLACED EXTERNALLY OF SAID INCINERATOR WITHOUT CONTACTING SAIDCOMBUSTION CHAMBER.